Nasal positive pressure device

ABSTRACT

The present invention relates to apparatus for treating sleep apnoea. More specifically, the present invention provides a nasal positive airway pressure device which is reliable and comfortable to wear and, consequently, more acceptable to the patient. The nasal device has inflatable cuffs worn in a patient&#39;s nasal cavities. A pair of inflating tubes are in gaseous communication with the interior of a respective one of the inflatable cuffs and when pressurised gases flow through each of the inflating tubes, each of the cuffs inflate to retain the cuff within each of the nasal cavities of the patient.

BACKGROUND TO THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to apparatus for treating sleepapnoea. More specifically, the present invention provides a nasalpositive airway pressure device which is reliable and comfortable towear and, consequently, more acceptable to the patient.

[0003] 2. Summary of the Prior Art

[0004] Obstructive Sleep Apnoea (OSA) is a sleep disorder that affectsup to at least 5% of the population in which muscles that normally holdthe airway open relax and ultimately collapse, sealing the airway. Thesleep pattern of an OSA sufferer is characterised by repeated sequencesof snoring, breathing difficulty, lack of breathing, waking with a startand then returning to sleep. Often the sufferer is unaware of thispattern occurring. Sufferers of OSA usually experience daytimedrowsiness and irritability due to a lack of good continuous sleep.

[0005] In an effort to treat OSA sufferers, a technique known asContinuous Positive Airway Pressure (CPAP) was devised. A CPAP deviceconsists of a gases supply (or blower) with a conduit connected tosupply pressurised gases to a patient, usually through a nasal mask. Thepressurised air supplied to the patient effectively assists the musclesto keep the patient's airway open, eliminating the typical OSA sleeppattern.

[0006] The procedure for administering CPAP treatment has been welldocumented in both the technical and patent literature. Briefly stated,CPAP treatment acts as a pneumatic splint of the airway by the provisionof a positive pressure, usually in the range 4 to 20 cm H₂O. The air issupplied to the airway by a motor driven blower whose outlet passes viaan air delivery hose to a nose (or nose and/or mouth) mask sealinglyengaged to a patient's face by means of a harness or other headgear. Anexhaust port is provided in the delivery tube proximate to the mask.More sophisticated forms of positive airway pressure devices, such asbi-level devices and auto-tritating devices, are described in U.S. Pat.No. 5,148,802 of Respironics, Inc. and U.S. Pat. No. 5,245,995 ofRescare Limited, respectively.

[0007] U.S. Pat. No. 5,477,852 of Airways Ltd, Inc. discloses a nasalpositive airway pressure device that has a pair of nasal members eachhaving a cannula tip to be inserted into the nares of the patient. Eachcannula is tapered from a substantially circular cross-section outsidethe patient's nostril to a substantially oval cross-section at the tipinserted into the nostril. An inflatable cuff surrounds each cannulawith the interior space of the cuff communicating with the lumen of thecannula through at least one aperture in the sidewall of the cannula.The nasal members are connected to one or more flexible hoses that, inturn, are connected to a source of positive air pressure. In use,positive air pressure is supplied to each cannula tip through the airhoses and nasal members. The positive air pressure inflates the cuffs tohold the nasal members in place and to effect treatment. The nasaldevice of U.S. Pat. No. 5,477,852 are attached to headgear that islocated about a patient's head. This headgear could be considered bymany patient's as cumbersome and uncomfortable.

[0008] Conventional nasal masks used for administrating CPAP treatmentare also considered uncomfortable and cumbersome, also prior art nasalmasks and the like are noisy, due to air leaks. These disadvantages inmany cases are a formidable obstacle to patient acceptance of suchtreatment. Therefore, a substantial number of patients either cannottolerate treatment or choose to forego treatment. It is believed asubstantial number of such patients could benefit from a nasal positiveairway pressure apparatus that is more convenient to use and comfortableto wear, thereby resulting in increased treatment compliance.

SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to attempt to provide anasal positive pressure device which goes some way to overcoming theabovementioned disadvantages in the prior art or which will at leastprovide the industry with a useful choice.

[0010] In a first aspect the present invention consists in a device fordelivering a supply of gases to a patient comprising or including:

[0011] a pair of nasal members, the distal end of each said nasal memberdefining a cannula,

[0012] a pair of inflatable cuff members, each said cuff membersurrounding at least a portion of each of said cannula,

[0013] a pair of inflating tubes each in gaseous communication with theinterior of a respective one of said cuff members, said communicationprovided through an aperture in each of said cuff member in which arespective one of said inflating tubes extends there through,

[0014] a source of pressurised gases connected to said inflating tubesto deliver pressurized air to the interior of said cuff members,

[0015] wherein, in use, when a respective one of said cuff members isinserted within a respective nasal cavity of said patient and when saidpressurised gases flow through each of said inflating tubes, each ofsaid cuff members inflate to retain said cuff members within each ofsaid nasal cavity of said patient.

[0016] To those skilled in the art to which the invention relates, manychanges in construction and widely differing embodiments andapplications of the invention will suggest themselves without departingfrom the scope of the invention as defined in the appended claims. Thedisclosures and the descriptions herein are purely illustrative and arenot intended to be in any sense limiting.

[0017] The invention consists in the foregoing and also envisagesconstructions of which the following gives examples.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] One preferred form of the present invention will now be describedwith reference to the accompanying drawings.

[0019]FIG. 1 is a block diagram of a humidified continuous positiveairway pressure system as might be used in conjunction with the presentinvention,

[0020]FIG. 2 is a front view of the nasal plugs and associated tubing ofone embodiment of the present invention, where the nasal plugs are madefrom a foam type material,

[0021]FIG. 3 is a close-up front view of the two nasal plugs of FIG. 2,

[0022]FIG. 4 is a cross-sectional view of a nasal plug of FIG. 2 throughAA as shown in FIG. 3,

[0023]FIG. 5 is a front view of one of two nasal plugs of a furtherembodiment of the present invention, where the nasal plugs are made froma silicon type material,

[0024]FIG. 6 is a cross-sectional view of the nasal plug through BB asshown in FIG. 5,

[0025]FIG. 7 is a front view of the nasal plugs and associated tubing ofyet another embodiment of the present invention, where the nasal plugsare inflatable cuffs,

[0026]FIG. 8 is a front view of one the inflatable cuffs of FIG. 7,

[0027]FIG. 9 is a cross-sectional view of the inflatable cuff, throughCC as shown in FIG. 8, when the cuff is in the inflated condition,

[0028]FIG. 10 is a cross-sectional view of the inflatable cuff, throughCC as shown in FIG. 8, when the cuff is in the deflated condition,

[0029]FIG. 11 is a perspective view of the nasal flap, nasal plugs andassociated tubing of still a further embodiment of the presentinvention, where the nasal flap is in the in use, closed position,

[0030]FIG. 12 is a front view of the nasal flap, nasal plugs andassociated tubing of FIG. 11, where the nasal flap is in the in use,closed position,

[0031]FIG. 13 is a side view of the nasal flap, nasal plugs andassociated tubing of FIG. 11, where the nasal flap is in the in use,closed position,

[0032]FIG. 14 is a perspective view of the nasal flap, nasal plugs andassociated tubing of FIG. 11, where the nasal flap is in the openposition,

[0033]FIG. 15 is a front view of the nasal flap and nasal plugs of FIG.11, where the nasal flap is in the open position,

[0034]FIG. 16 is a side view of the nasal flap and nasal plugs of theforth form of the present invention, where the nasal flap is in the openposition,

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] It will be appreciated that the improvements to nasal plugs asdescribed in the preferred embodiments of the present invention can beused in respiratory care generally or with a ventilator, but will now bedescribed below with reference to their use in a humidified ContinuousPositive Airway Pressure (CPAP) system.

[0036] CPAP System

[0037] With reference to FIG. 1 a CPAP system is shown in which apatient 1 is receiving humidified and pressurised gases through thenasal device 2, such as nasal cannulae, that are connected to ahumidified gases transportation pathway or inspiratory conduit 3. Itshould be understood that delivery systems could also be VPAP (VariablePositive Airway Pressure) and BiPAP (Bi-level Positive Airway Pressure)or numerous other forms of respiratory therapy. Inspiratory conduit 3 isconnected to the outlet 4 of a humidification chamber 5 that contains avolume of water 6. Inspiratory conduit 3 may contain heating means orheater wires (not shown) that heat the walls of the conduit to reducecondensation of humidified gases within the conduit. Humidificationchamber 6 is preferably formed from a plastics material and may have ahighly heat conductive base (for example an aluminium base) which is indirect contact with a heater plate 7 of humidifier 8. Humidifier 8 isprovided with control means or electronic controller 9 which maycomprise a microprocessor based controller executing computer softwarecommands stored in associated memory.

[0038] Controller 9 receives input from sources such as user input meansor dial 10 through which a user of the device may, for example, set apredetermined required value (preset value) of humidity or temperatureof the gases supplied to patient 1. The controller may also receiveinput from other sources, for example temperature and/or flow velocitysensors 11 and 12 through connector 13 and heater plate temperaturesensor 14. In response to the user set humidity or temperature valueinput via dial 10 and the other inputs, controller 9 determines when (orto what level) to energise heater plate 7 to heat the water 6 withinhumidification chamber S. As the volume of water 6 within humidificationchamber S is heated, water vapour begins to fill the volume of thechamber above the water's surface and is passed out of thehumidification chamber 5 outlet 4 with the flow of gases (for exampleair) provided from a gases supply means or blower 15 which enters thechamber through inlet 16. Exhaled gases from the patient are exhaustedto the ambient surroundings.

[0039] Blower 15 is provided with variable pressure regulating means orvariable speed fan 21 that draws air or other gases through blower inlet17. The speed of variable speed fan 21 is controlled by electroniccontroller 18 (or alternatively the function of controller 18 couldcarried out by controller 9) in response to inputs from controller 9 anda user set predetermined required value (preset value) of pressure orfan speed via dial 19.

[0040] Nasal Plugs

[0041] In a general form, the nasal device 2 generally consists ofY-shaped connector piece that connects the nasal device to the breathingcircuit, transportation passageway or conduit 3, which is connected tothe source of pressurised gas. Each arm of the Y-shaped connector isconnected to a nasal tube, which are each connected to nasal members.The nasal members have a tapered end terminating in an aperture(cannula), the tapered end has disposed about it nasal plugs. In use,when a patient inserts each of the nasal plugs into their nasal cavitiesand positive pressure ventilation therapy is commenced, pressurisedgases pass through the conduit 3, into the Y-shaped connector, througheach of the nasal tubes exiting into the patient's nostrils through eachnasal cannula, thereby administering positive pressure ventilationtherapy to the patient.

[0042] Referring to FIGS. 2 to 4, there is shown a nasal positive airwaypressure device 30 in accordance with a first embodiment of the presentinvention. Device 30 consists of a Y-shaped connector piece 31 (that isconnected to the gases outlet end of the conduit 3), and a pair of nasaltubes 32, 33 each terminating in a nasal member 34, 35. The Y-shapedconnector 31 and each of the nasal members 34, 35 are hollow cylindersor tubes that allow for the flow of gases therein. The nasal membersterminate in an aperture that is the outlet of pressurised gases fromthe ventilation system into the patient's nasal cavities. The end ofeach nasal member 34, 35 defines a cannula, which is basically a taperedend 36 terminating in an aperture. Fitted about each cannula 36 is anasal plug 37, 38 configured and dimensioned to fit within the nasalcavities of a patient. In the first form of the present invention thenasal plugs 37 and 38 are made of a foam type material, preferably aclosed-cell foam that has been moulded into the shape of a nostril, thatshape being a generally frustoconical.

[0043] The Y-connector 31 and nasal members 34, 35 are each moulded froma polycarbonate type material, although other substantially rigidmaterials may be used, such as rigid plastics or metal. Suitableplastics include homopolymers, copolymers, blends and mixtures ofpolystyrene, ABS, polycarbonate, acrylics, or polyethylene. Suitablemetals include stainless steel, titanium, aluminium and alloys thereofOne end of each nasal tube 32, 33 is fitted over the arms 39, 40 of theY-connector 31 and the other end of each nasal tube 32, 33 is adapted tobe connected to each nasal member 34, 35, for example the nasal membermay be fitted within the nasal tubes 32, 33. These fittings may be ofany convenient manner suitable for coupling without substantial loss ofgas pressure, such as by friction fit, snap fit, gluing, welding,threading or the like. The foam nasal plugs 31, 38 are fixed about thecannulae 36 by appropriate fixing means, for example by gluing, in amanner that preserves gas pressure.

[0044] The nasal tubing 32, 33 are conduits 44 that is, in the preferredform, molded from an elastomeric material such as a Polyethylene/EVAmixture or silicon rubber. The conduit preferably has a “ribbed” “orcorrugated” construction to allow bending, (the ribs are referenced as45). This conduit construction may be accomplished by blowing the moltenelastomeric material to form an endless cylinder that is forced outwardsagainst the internal surface of a rotating mould that impresses the ribsonto the conduit. The conduit 44 may also have within it a helicallywound heater wire (not shown) that preferably sits against or adjacentto the internal wall of the conduit along its length. The purpose ofhaving a conduit with a heater wire is to reduce the condensation of thegases within the conduit. The nasal tubing 32, 33 being a “ribbed”conduit provides the advantage of being able to be easily manipulated bythe patient for additional patient comfort.

[0045] In use, the patient need only apply pressure to the sides of thefoam nasal plugs 37, 38 thereby depressing the foam deforming the shapeof each of the nasal plugs so that each is easily insertable into eachnasal cavity. Once each plug is within each cavity the foam will expandto its original form where the external surface of the foam abuts theinternal surface of the patient's nasal cavity, thereby filling the areawithin each nostril. The foam nasal plug provides a seal between thecavity and the cannula, effectively eliminating gases leakage, as theexpanding foam provides an outward force upon the inner surface of eachof the patient's nasal cavities, which also prevents each plug fromfalling from the nasal cavity.

[0046] Nasal members 34, 35 have disposed in them at least one, butpreferably a number of, small holes (not shown) that act as vents toexhaust the gases that are exhaled by the patient. The holes and thusthe nasal members may be covered with an appropriate type of materialthat acts as a diffuser.

[0047] In a further form of the nasal device of the present invention,the nasal plugs may be constructed from a silicon type material. Withreference to FIGS. 5 and 6, the, nasal device in this form is almostidentical to that as shown in FIG. 2, the difference being the nasalplugs are manufactured from a silicon type material that is formed in aninverted U-shape. The nasal plug and nasal member, as shown in FIG. 6,is a cross-section through BB of FIG. 5. The silicon nasal plug 41 isadapted to be connected to the tapered end 42 of the respective nasalmember 40. This connection may be provided by any appropriate means asdiscussed earlier in relation to the embodiment of the nasal plugs, butmore preferably by a type of glue.

[0048] Again, to allow for exhaust and diffusion of exhaled gases fromthe patient each of the nasal members (of which only one, labelled 40,is shown in FIGS. 5 and 6 have disposed in them at least one, butpreferably a number of, small holes (not shown) that act as vents toexhaust the gases that are exhaled by the patient into the ambient air.The holes and thus the nasal members may be covered with an appropriatetype of material that acts as a diffuser.

[0049] The nasal plug 41 may be made from other appropriately flexiblematerials that will be deformed under a pressure applied by the user ofthe nasal device. In use, as a patient inserts the U-shaped plugs intohis or her nares the arms of each of the U-shaped plugs are compressed,effectively reducing the space 43 between the tapered end 42 and theinterior surface of the nasal plug 41. Once the plugs are completelyinside the nares, the arms of each U-shaped plug expand to their naturalposition, causing the plugs to be retained within the nares by way offriction.

[0050] In both of the abovementioned forms the nasal plugs provide agood seal within the patient's nasal cavities, thereby reducing theeffects of gases leakage. As the nasal plugs are deformable, they areeasily fitted by the patient and provide greater patient comfort when inuse. In addition, the forces of the expanding materials, once inserted,hold the nasal plugs within the nasal cavities in a manner that is morecomfortable to the patient than prior treatment devices.

[0051] Inflatable Cuffs

[0052] In accordance with a further embodiment of the present invention,FIGS. 7 to 9 show a nasal device 50 that utilises inflatable cuffs 51,52. The cuffs are attached by appropriate means, for example by mouldingor gluing or the like, to the nasal members 53, 54. The nasal members53, 54 are adapted to be connected to nasal tubes 55, 56 and the nasaltubes to the Y-connector as described above.

[0053] Each inflatable cuff 51, 52 surrounds the tapered end 58 (seeFIG. 8) and provides a force, when in use, within the nasal cavity, tohold the tapered end 58 in position within the patient's nares in amanner to be explained below. Each tapered end 58 of the nasal members53, 54 are preferably substantially oval or elliptical in cross-sectionat the open end that is distal to nasal members 53, 54, and graduallytapers to a substantially circular cross-section outside the patient'snares. The inflatable cuffs 51, 52 surrounding each tapered end 58 aremade of a plastics material, and a small inflation tube 59, 60, madefrom a flexible plastics material communicates with the interior spaceof each cuff, preferably through the cuff wall. Both inflation tubes 59,60 are connected to an inflation device, where when the inflation deviceprovides gases to the tubes (59, 60) the cuffs are inflated with thegases. FIG. 9 shows one such inflatable cuff 51 in cross-section whenthe cuff is inflated in an “in use” form, whereas FIG. 10 shows one suchcuff 51′ in cross-section when the cuff is the deflated “insertion”form.

[0054] The inflation device that could be used to provide gases to theinflation tubes may be a non-return valve with a fitting at one end, inwhich a plastic syringe (without the needle) could be placed. Thesyringe can then be used to force air into each of the cuffs. When thesyringe is removed the non-return valve would keep the air in the cuffs.This is similar to the inflation system on an ET tube. To deflate thecuff, the syringe can be inserted into the inflating tubes and valve anddraw the gases from the cuff.

[0055] Alternatively, a further inflation device is anticipated which isa small pump mechanism. This would involve having a plastic gasesholding compartment with two non-return valves attached on either sideof the compartment. One valve would allow air to pass into thecompartment from the atmosphere, and once the compartment is compressed,for example, by the patient's fingers, gases are forced through thesecond non-return valve, into the inflating tubes, inflating the cuffs.To deflate the cuffs, the pump mechanism would be supplied with a bleedvalve, that is preferably hand operated.

[0056] In use, when the patient wishes to commence positive pressureventilation therapy, he or she must place each cuff within his or hernasal cavities and start the inflation device. As air flows through theinflation tubes 59, 60 the cuffs 51, 52 will inflate and provide a forceagainst the internal walls of the nasal cavities, preventing the cuffsfrom falling from the cavities. Again, this embodiment of the nasalplugs of the present invention has the advantage of providing thepatient with a comfortable alternative to prior art nasal devices.

[0057] Nasal Snap Flap

[0058] In accordance with a fourth form of the present invention, FIGS.11 to 16 show a nasal device 60 that utilises an engagement meanslocated about nasal cannulae to engage and secure the cannulae withinthe nares of a patient. The engagement means is a nasal sealing flap 61.The flap 61 in its natural bias is tapered, the wide-open end of whichis shaped to conform to the facial contours of a patient's nose aroundthe outside of the nose. Thus in a closed form, as shown in FIGS. 11 to13, the flap provides a cup-like device that is fitted around thepatient's nose and prevent the nasal device 60 from falling from thepatients nose. In the open form, that allows for placement and fittingof the nasal device 60, the flap 61 is intended to be in a bent backposition, as shown in FIGS. 14 to 16, to aid insertion of the nasalcannulae 63, 64 into the patient's nares.

[0059] The nasal device comprises the nasal sealing flap 61 connected byappropriate means to a nasal member 62 that terminates in at least onenasal cannula, although in the preferred form two cannulae 63, 64 areprovided, one for each of the patient's nares. The flap 61 and cannulae63, 64 may be integrally formed or the flap 61 may be attached about thecannulae 63, 64 (by appropriate means, such as gluing) after thecannulae have been formed. Furthermore, the cannulae 63, 64, flap 61 andnasal member 62 may all be integrally formed by injection moulding orthe like methods. The cannulae 63, 64 extend through the proximate endof the flap 61, so that in use, upon placing the flap about thepatient's nose the cannulae extend into the nasal cavities of thepatient's nose. The other end of the nasal member 62 is connected, againby appropriate fixing means, such as by friction fit, snap fit, gluing,welding, threading or the like, to a nasal tube 65.

[0060] The nasal tube 65 is a conduit that is, in the preferred form,moulded from an elastomeric material such as a Polyethylene/EVA mixtureor silicon rubber. The conduit preferably has a “ribbed” “or corrugated”construction to allow bending that is constructed as described abovewith relation to the tubing 32, 33 of FIG. 2. The nasal tube 65 ispreferably connected to the inspiratory conduit 3 and thus to the restof the ventilation system as detailed with reference to FIG. 1 above. Inan alternative form the nasal tube 65 and conduit 3 may be one tube.

[0061] In use, to attach the nasal device to the nose and nares, thepatient bends back the flap 61 to the open position, as shown in FIGS.14 to 16, and inserts the nasal cannulae 63, 64 into each nostril. Toenable the retaining of the cannulae 63, 64 within the nares the flap 61is bent into the closed position, the flap 61 providing a cup-like sealaround the patient's nose. The flap is bent back into the open positionto enable removal from the patient, by simply pressing on its outerperiphery 66, until it snaps into the bent back position, in which itwill stay unaided. The flap 61 may be adjusted into its operationalposition by pressing on its outer periphery 66 until it snaps forward topress against the outside of the nose.

[0062] It will be appreciated that as well as providing a substantiallyairtight seal the flap provides enough compressive force on the nose tokeep the nasal device and conduit in place without the need for straps.This allows the administering of positive airway pressure ventilationtherapy to be considerably less obtrusive than traditional methods.

[0063] In all forms of the nasal device as discussed above, the frictionbetween the plugs or cuff of the device and the interior surface of thepatient's nares prevents the plugs or cuffs from falling from thepatient's nares. Although it is appreciated that headgear could be usedto ensure securement of the nasal device to the patient. Thus, thedevice may be secured to the head of the user with headgear (not shown)by attaching straps of the headgear at an appropriate point along thelength of each nasal tube or at the nasal members. Furthermore, a clipor the like could be used to attach the tubing associated with the nasaldevice to the patient's clothes.

What is claimed is:
 1. A device for delivering a supply of gases to apatient comprising or including: a pair of nasal members, the distal endof each said nasal member defining a cannula, a pair of inflatable cuffmembers, each said cuff member surrounding at least a portion of each ofsaid cannula, a pair of inflating tubes each in gaseous communicationwith the interior of a respective one of said cuff members, saidcommunication provided through an aperture in each of said cuff membersin which a respective one of said inflating tubes extends there through,a source of pressurised gases connected to said inflating tubes todeliver pressurized air to the interior of said cuff members, wherein,in use, when a respective one of said cuff members is inserted within arespective nasal cavity of said patient and when said pressurised gasesflow through each of said inflating tubes, each of said cuff membersinflate to retain said cuff members within each of said nasal cavity ofsaid patient.
 2. A device for delivering a supply of gases to a patientaccording to claim 1 wherein said device includes: a pair oftransportation means, and connecting means, wherein said nasal membersare each connected to said transportation means to supply said gases toeach of said cannula, and said connecting means is substantiallyY-shaped, the arms of said Y-shaped connector adapted to be connected toa respective one of said pair of transportation means.
 3. A device fordelivering a supply of gases to a patient according claim 2 wherein saidconnecting means is adapted to be connected to a supply of said gases.4. A device for delivering a supply of gases to a patient accordingclaim 2 wherein said connecting means is connected to said gases supplyby way of a gases pathway that is a flexible conduit that defines apassage for the flow of gases from said patient
 5. A device fordelivering a supply of gases to a patient according to claim 1 whereinsaid source of pressurised gases comprises a valve connected to each ofsaid inflating tubes, and a gases compression means, which pushes gasesthrough said valve and into said inflating tubes to inflate said cuffs.6. A device for delivering a supply of gases to a patient according toclaim 5 wherein said valve is a non-return valve.
 7. A device fordelivering a supply of gases to a patient according to claim 5 whereinsaid gases compression means is a syringe comprising or including: abody part, and reciprocating part, adapted to be connected andreciprocatable within said body part and a nib member, wherein, in use,said body part is filled with gases from the ambient air by pulling saidreciprocating part partially out of said body part drawing said gasesinto said body part, and inserting said nib into said inflating tubesand pushing said reciprocating part back into said body part causingsaid gases to be pushed past said valve and into said inflating tubes.8. A device for delivering a supply of gases to a patient according toclaim 1 wherein said source of pressurised gases is a pump mechanismcomprising or including: a first valve, receiving gases from theatmosphere, a gases compartment holding said gases, and a second valveconnected to each of said inflating tubes, which said gases pass throughon compression of said gases compartment and into said inflating tubes.9. A device for delivering a supply of gases to a patient according toclaim 8 wherein said first and second valves are non-return valves. 10.A device for delivering a supply of gases to a patient according toclaim 1 wherein said pair of inflating tubes are flexible conduits of asmall diameter that are fitted to and extend into a respective one ofsaid inflatable cuffs.
 11. A device for delivering a supply of gases toa patient according to claim 1 wherein said device includes:humidification means in fluid communication with said supply of gases,adapted to humidify said gases, and gases pathway in fluid communicationwith said humidification means and adapted to convey said gases to saidgases pathway.
 12. A device for delivering a supply of gases to apatient according to claim 1 wherein said pair of nasal members have atleast one aperture extending therethrough, said aperture acting as avent of gases exhaled from said patients nasal cavities.